Photoelectric devices generally refer to photoconductive devices operating by utilizing the photosensitivity of semiconductors or photocells and semiconductor light-emitting devices operating by utilizing the photovoltaic effect of semiconductors. Photoelectric devices such as light guide, photocell, light-emitting diode, phototransistor and thermistor are widely applied in various technical fields.
Most of photoelectric devices have to utilize a barrier film layer to protect against air or water vapor so as to increase the service life of devices.
Hereinafter organic light-emitting display devices are described by way of example. Organic light-emitting materials are applicable in the field of display to manufacture organic light-emitting displays. A decrease in the service life of the organic light-emitting display device is mainly attributed to three factors including: first of all, electrodes in the organic light-emitting device mostly are formed of a metal material such as Al, Mg and Ca which are usually active and thus liable to be corroded in the air or in other atmosphere containing oxygen; secondly, hydroxy compounds generated by an oxidation action between oxygen and a light-emitting layer act as an effective quenching agent which can considerably decrease the luminescence quantum efficiency of the organic light-emitting display device; moreover, the heat produced during the operation of organic light-emitting device can further aggravate the degradation of light-emitting materials, electrode materials and the like of devices in the air.
Therefore, organic light-emitting devices are usually packaged by forming barrier film layers utilizing materials such as silicon nitride to protect against air and water vapor, which can greatly increase the service life of devices.